<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<form action="day02_data.php" method="post">
    <p>
        用户名：<input type="text" name="name" id="loginName">
        <span id="tip"></span>
    </p>
    <p>
        密码：<input type="password" name="password">
    </p>
    <p>
        <input type="submit" value="提交">
    </p>
</form>
<script src="jquery-3.3.1.min.js"></script>
<script>
    $("#loginName").blur(() => {
        var name = $("#loginName").val();
        $.get("day02_data.php?name=" + name, (data) => {
            $("#tip").text(data);
        })
    })
</script>
</body>
</html>